Mk3 motion ratios.

[LordDigital]

^ I don't think it had anything to do with fire. I think they have difficult to detect corrosion and can spontaneously fracture. (Of course if you then have a high speed magnesium hub spinning and grinding on the road, maybe the fire hazard becomes an issue too? Shudder...).

There was a magnesium model of the TRD Sports T3 (maybe different model number, but similar style) like what Duane (upgraded supra) had before he went CCWs.

Magnesium wheels were banned by FIA (and consequently by many other Motorsports authorities) ,not only because they burned spectacularly but also because magnesium does not need oxygen to burn and when it burns the temperature is extremely high.

Are you sure about the 50% difference? That sounds quite high ,IIRC magnesium wheels compared to high end alloys such as SSR competition or my WedSports were less than 30% lighter...

 

[Dimman]

Are you sure they are banned? Rays still makes forged magnesium wheels for racing (F1, ALMS, Super GT) applications. I was under the impression that cost played a bigger role than fire since they are basically 'disposable' in a racing environment due to fatigue and corrosion giving them a rather short service life.

http://www.rays-msc.com/html/racing_wheels.html

Also, the old TRD ones (no weights on the mag ones.)

http://www.trdparts.jp/english/parts_wheel-sport.html

 

[te72]

Magnesium wheels were banned by FIA (and consequently by many other Motorsports authorities) ,not only because they burned spectacularly but also because magnesium does not need oxygen to burn and when it burns the temperature is extremely high.

Are you sure about the 50% difference? That sounds quite high ,IIRC magnesium wheels compared to high end alloys such as SSR competition or my WedSports were less than 30% lighter...

Not positive on the weight difference, but if speaking apples and apples (cast vs cast, forged vs forged), magnesium is still a notable amount of weight less than a comparative aluminum alloy. I've always wondered why I don't see more titanium wheels out there, it is a fairly light alloy, correct? Fragility (or a tensile/impact strength issue) perhaps?

As for magnesium being banned, look up the 1955 Le Mans incident. Isn't pretty when emergency crews don't know how to fight an unfamiliar fire... http://en.wikipedia.org/wiki/1955_24_Hours_of_Le_Mans

Edit: Looked at the TRD setup, thanks Dimman. Bit too skinny and the offsets aren't quite right, but if someone happened to have a set of those lying around, they would be really nice for a stock car.

 

[Dimman]

Titanium is sensitive to notch damage (small nick in it will become a stress riser and rapidly fatigue), and has poor stiffness to weight.